42238381 has 2 divisors, whose sum is σ = 42238382. Its totient is φ = 42238380.

The previous prime is 42238367. The next prime is 42238393. The reversal of 42238381 is 18383224.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 39262756 + 2975625 = 6266^2 + 1725^2 .

It is a cyclic number.

It is not a de Polignac number, because 42238381 - 2⁷ = 42238253 is a prime.

It is a super-2 number, since 2×42238381² = 3568161659002322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42238321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21119190 + 21119191.

It is an arithmetic number, because the mean of its divisors is an integer number (21119191).

Almost surely, 2^42238381 is an apocalyptic number.

It is an amenable number.

42238381 is a deficient number, since it is larger than the sum of its proper divisors (1).

42238381 is an equidigital number, since it uses as much as digits as its factorization.

42238381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9216, while the sum is 31.

The square root of 42238381 is about 6499.1061693128. The cubic root of 42238381 is about 348.2590581060.

The spelling of 42238381 in words is "forty-two million, two hundred thirty-eight thousand, three hundred eighty-one".